Demi Lovato leaps to her second No. 1 on Billboard's Pop Songs radio airplay chart, as "Sorry Not Sorry" jumps 5-1 on the latest tally, dated Nov. 4.   "Sorry" soars to No. 1 on Pop Songs with the greatest positional leap to the top in nearly three years; Tove Lo's "Habits (Stay High)" surged 5-1 on the Nov. 15, 2014, chart. "Sorry" also claims the chart's greatest gain in plays, hiking by 19 percent.   Meanwhile, last week's new Pop Songs No. 1, Taylor Swift's "Look What You